1. Field of the Invention
The present invention relates to a pattern-forming method.
2. Discussion of the Background
As miniaturization of various types of electronic device structures such as semiconductor devices and liquid crystal devices proceeds, finer patterning in lithography techniques has been demanded. For the present, formation of fine patterns with a line width of about 90 nm is enabled using for example, an ArF excimer laser; however, still finer pattern formation will be hereafter required.
Conventionally, pattern-forming methods in which a chemical amplification type resist composition is used have been extensively employed for forming such fine patterns. The chemical amplification type resist composition contains an acid generating component that generates an acid upon exposure to light, and further a resin component that has solubility in developing solutions which is to be changed by an action of this acid (see, JP-A No. S59-45439), and is capable of forming patterns using the difference the rate of dissolution of a light-exposed site and that of a light-unexposed site. A variety of compositions have been developed as the chemical amplification type resist composition such as radiation sensitive compositions containing a lactone-containing (meth)acrylic polymer (see, JP-A Nos. H9-90637, H10-274852, 2000-26446 and 2009-196944), radiation sensitive compositions containing a acrylic acid ester derivative having a cyclic sulfonyl structure (see, JP-A No. 2009-196944), and the like.